This invention relates generally to high temperature lubrication and more specifically to lubricant compositions and their use. The compositions contain complex metal chalcogenides which are compatible with various steels and alloys and which provide antiwear and extreme pressure properties.
Commonly used solid lubricants or solid lubricant additives are graphite, molybdenum disulfide, polytetrafluoroethane, lead oxide, boron nitride, alkaline metal borates, arsenic thioantimonate, and so forth. These solid lubricants have certain disadvantages, such as limited high temperature stability, hydrolytic instability, potential toxicity, inferior performance under high vacuum or high temperature, or undesirable by-products after exposure to high temperature. Antimony thioantimonate (SbSbS.sub.4) has excellent extreme pressure and antiwear properties when used as a lubricant additive as described, for example, in U.S. Pat. No. 3,965,016. In modern high temperature lubricating applications using various steels and alloys, lubricants having even better antiwear properties are desirable.